1. Field of the Invention
The present invention relates to a sample preprocessing system for a fluorescent X-ray analysis, which system includes a sample preprocessing apparatus for retaining on a surface of a substrate a substance to be measured that is found on the surface of the substrate, after such substance has been dissolved and subsequently dried, a transport apparatus for transporting the substrate, and a control apparatus for controlling the sample preprocessing apparatus and the transport apparatus, and an X-ray fluorescence spectrometric system utilizing such sample preprocessing system.
2. Description of the Prior Art
In this type of the X-ray fluorescence spectrometric system, it has been suggested to facilitate an easy operation of the system as a whole. See, for example, the Japanese Patent Application No. 2001-270604. According to the suggested X-ray fluorescence spectrometric system, a vapor phase decomposing apparatus and a sample recovery apparatus that constitute the sample preprocessing apparatus has its own automatically opening and closing shutter adapted to be properly opened or closed by a control apparatus when the substrate is to be transported into or out of the apparatus. While a reactive gas such as hydrogen fluoride is employed within the sample preprocessing apparatus, during a normal operation the automatically opening and closing shutters will not be opened when a high concentration of the reactive gas is present within the apparatus and, since even if they were to be opened, the apparatus has an inside pressure set to be lower than the pressure outside the apparatus, there is no possibility that the reactive gas within the apparatus may flow out of the apparatus to such an extent as to result in adverse influence on other apparatuses.
However, when by reason of, for example, an erroneous operation the automatically opening and closing shutter is opened while a certain concentration of the reactive gas is present within the apparatus and the inside pressure of the apparatus is not so low as compared with the pressure outside the apparatus, the reactive gas will flow outwardly of the apparatus and, as a result thereof, there is the possibility that the transport apparatus and/or the X-ray fluorescence spectrometer positioned outside the apparatus will be corroded with the service lifetime thereof consequently reduced.
The present invention has been devised with a view to substantially eliminating the inconveniences inherent in the conventional system discussed above and is intended to provide a sample preprocessing system for a fluorescent X-ray analysis, which system includes a sample preprocessing apparatus for retaining on a surface of a substrate a substance to be measured that is found on the surface of the substrate, after such substance has been dissolved and subsequently dried, a transport apparatus for transporting the substrate, and a control apparatus for controlling the sample preprocessing apparatus and the transport apparatus, wherein corrosion prevention and increase of the service lifetime are made in the transport apparatus or the like that is positioned outside the sample preprocessing apparatus.
Another important object of the present invention is to provide an X-ray fluorescence spectrometric system utilizing the sample preprocessing system of the type discussed above.
In order to accomplish the foregoing objects, the present invention in one aspect thereof provides a sample preprocessing system for a fluorescent X-ray analysis, which system includes a vapor phase decomposing apparatus, a sample recovery apparatus, a transport apparatus, and a control apparatus, all of which are discussed below. It is to be noted that the vapor phase decomposing apparatus and the sample recovery apparatus altogether constitute a sample preprocessing apparatus.
The vapor phase decomposing apparatus is operable to retain on a surface of a substrate a substance to be measured that is found on the surface of the substrate or a substance to be measured that is found on a surface of a film formed on the surface of the substrate or within the film, after such substance has been dissolved by a reactive gas and has subsequently been dried, in a decomposing chamber. The sample recovery apparatus is operable to drop a solution on the substrate having the surface on which the substance to be measures exists, to move the solution on the substrate surface while being retained by a holder, and to retain the substance to be measured on the substrate surface after having been recovered in the solution and then dried, in a recovery chamber. The transport apparatus is operable to transport the substrate from the decomposing chamber towards the recovery chamber. The control apparatus controls the vapor phase decomposing apparatus, the sample recovery apparatus, and the transport apparatus. A set of the vapor phase decomposing apparatus and the sample recovery apparatus includes an automatically opening and closing shutter, a differential pressure detecting means for detecting a pressure difference between inside and outside of the set and a concentration detecting means for detecting a concentration of the reactive gas within the set. The control apparatus is operable to open the automatically opening and closing shutter after it has ascertained that the pressure difference detected by the differential pressure detecting means and the concentration detected by the concentration detecting means are within respective predetermined ranges.
According to the present invention, since the control apparatus opens the automatically opening and closing shutter after it has ascertained that the pressure difference between inside and outside of the sample preprocessing apparatus detected by the differential pressure detecting means and the concentration of the reactive gas within the sample preprocessing apparatus detected by the concentration detecting means are within the respective predetermined ranges, there is no possibility that the reactive gas may flow from inside the sample preprocessing apparatus to the outside and, therefore, corrosion prevention and increase of the service lifetime of the transport apparatus and others that are positioned outside can be sufficiently attained.
The present invention in another aspect thereof provides an X-ray fluorescence spectrometric system including the sample preprocessing system for the fluorescent X-ray analysis discussed above, in combination with an X-ray fluorescence spectrometer for irradiating the substance to be measured, that is retained on the surface of the substrate by the vapor phase decomposing apparatus or the sample recovery apparatus, with primary X-rays to excite the substance to be measured and for subsequently measuring intensities of fluorescent X-rays emitted therefrom as a result of the excitation. In this X-ray fluorescence spectrometric system, the transport transports the substrate from the decomposing chamber towards the X-ray fluorescence spectrometer and also from the recovery chamber towards the X-ray fluorescence spectrometer, and the control apparatus controls the X-ray fluorescence spectrometer as well. Even with the X-ray fluorescence spectrometric system of the present invention, effects similar to those afforded by the sample preprocessing system of the present invention can be obtained.